SDETs

SDETs, or Software Development Engineers in Test, are professionals who apply software development practices to testing. Unlike traditional testers who primarily execute tests, SDETs design and build automated testing tools and test frameworks, and write code to test the product at various levels.

Core responsibilities include creating, maintaining automated test suites, building test harnesses, and integrating tests into continuous integration pipelines. SDETs work on unit, integration, API, and end-to-end tests; they may also contribute to manual exploratory testing to uncover edge cases. They collaborate with developers, product managers, and QA engineers to ensure testability and reliable delivery.

Skills and tools: proficient in one or more programming languages (for example Java, C#, Python, or JavaScript); experience with testing frameworks (JUnit, TestNG, pytest, Mocha) and automation tools (Selenium, Cypress, Appium); familiarity with CI/CD (Jenkins, GitHub Actions); version control; debugging and performance testing; knowledge of design patterns and software architecture.

Role and workflow: SDETs participate early in design reviews, emphasize testability, and write code that doubles as production and test code when possible. They maintain test infrastructure, analyze failures, and advocate for reliable metrics. They align with agile or DevOps practices and strive for test automation coverage and speed.

Industry use and distinctions: The term SDET emphasizes the blend of software development and testing; roles vary by company. Some teams distinguish SDETs from SDEs (software developers) and from QA engineers, while others merge responsibilities under one title. The overarching goal is to improve quality through automated, maintainable tests.